flags! {
#[repr(u32)]
pub enum UsageFlags {
BACK_BUFFER = 1 << (2 + 4),
DISCARD_ON_PRESENT = 1 << (5 + 4),
READ_ONLY = 1 << (4 + 4),
RENDER_TARGET_OUTPUT = 1 << (1 + 4),
SHADER_INPUT = 1 << (0 + 4),
SHARED = 1 << (3 + 4),
UNORDERED_ACCESS = 1 << (6 + 4),
}
}